Background: Evidence of inequalities in obesity and overweight is available mostly from national studies. This article provides a broad international comparison of inequalities by education level and socio-economic status, in men and women and over time.
Methods: Data from national health surveys of 11 OECD countries were used. The size of inequalities was assessed on the basis of absolute and relative inequality indexes. A regression-analysis approach was used to assess differences between social groups in trends over time.
Results: Of the countries examined, USA and England had the highest rates of obesity and overweight. Large social inequalities were consistently detected in all countries, especially in women. Absolute inequalities were largest in Hungary and Spain with a difference of 11.6 and 10% in obesity rates in men, and 18.3 and 18.9% in women, respectively, across the education spectrum. Relative inequalities were largest in France and Sweden with poorly educated men 3.2 and 2.8 times as likely to be obese as men with the highest education (18 and 17 times for women in Spain and Korea, respectively). Pro-poor inequalities in overweight were observed for men in USA, Canada, Korea, Hungary, Australia and England. Inequalities remained virtually stable during the last 15 years, with only small variations in England, Korea, Italy and France.
Conclusion: Large and persistent social inequalities in obesity and overweight by education level and socio-economic status exist in OECD countries. These are consistently larger in women than in men.
Keywords: International comparison; obesity; socio-economic inequalities.